Groundwater Flow in a Bog-Fen Complex, Lost River Peatland, Northern Minnesota

Abstract

(1) The hydrogeology of a spring-fen mound, water track, and raised bog in the remote Lost River peatland, northern Minnesota, was investigated by measurements of the groundwater levels and chemistry of groundwater in observation wells. (2) Water-level measurements indicate that all the major physiographic features in the mire-a raised bog, spring fen, and intervening water track-are zones of groundwater discharge during parts of the year. (3) Sodium concentrations in peat pore-water change linearly with depth, indicating the upward advection of solutes in ground water. (4) Alkalinity and pH profiles indicate that acidic bog waters are neutralized below 0 5 m in the peat profile. A small change in the volume of groundwater discharge in the peatland may therefore be sufficient to neutralize the acidic waters on the bog surface and greatly affect the vegetation.